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The unusual horned comet, called the “Devil’s comet” and attracting attention with a series of explosions, will make its closest approach to Earth around 03:00 in the morning on Sunday.
Although the comet has not been visible to those in the Northern Hemisphere since the first week of May, skywatchers in the Southern Hemisphere have a better chance of spotting the blurry object through binoculars or a telescope.
Exactly why the dynamic comet became explosively active in a shape that drew comparisons to the Millennium Falcon spacecraft in the “Star Wars” movies is still a mystery to scientists. However, the celestial body completes only one orbit around the sun approximately every 71 years, similar to Halley’s comet; This makes the possibility of observing it up close a once-in-a-lifetime opportunity.
Given that the comet will not pass by Earth for decades, astronomers’ collective observations could provide important information about its true nature and behavior.
The object officially known as Comet 12P/Pons-Brooks made its closest pass to the sun on April 21, coming within 74.4 million miles (119.7 million kilometers) of our star.
The comet will make its closest pass by Earth on Sunday, but it will be more than 143 million miles (230 million kilometers) from our planet and will not pose a risk. For reference, the Sun is 93 million miles (149 million kilometers) from Earth.
Astronomer Dr. of the Lowell Observatory in Arizona. The comet’s brightness peaked in late April and has been waning steadily for three to four weeks, Dave Schleicher said.
Astronomer Dr. D., a postdoctoral research fellow at Lowell. “For people living below the equator, the coming weeks and months may be their first good chance to see this thing since the 1950s,” Teddy Kareta said.
Two prolific explorers, Jean-Louis Pons and William Robert Brooksindependently observed the devil’s comet – Pons in 1812 and Brooks in 1883. But the comet likely made many trips around the sun over thousands of years, long before astronomers thought of comets as “something weird in the atmosphere,” Schleicher said.
Astronomers estimate the large comet to be between 6.2 and 12.4 miles (10 to 20 kilometers) in diameter, Kareta said.
The rare visitor has a green appearance typical of most comets because it contains diatomic carbon molecules that absorb sunlight and emit a color that appears green from our perspective, Schleicher said.
A series of cosmic explosions
Pons-Brooks recently came to the attention of astronomers after exhibiting intriguing behavior that caused the comet to have a horned appearance and fly through our solar system.
The comet has experienced a series of explosions over the past eight months that have caused it to spew gas and dust. Although such oscillations are not uncommon in comets, and a crescent or Pac-Man shape has been observed in others, it is difficult to say what is normal for Pons-Brooks.
“I would say this is a little bit unusual in terms of the number of outbursts he’s had,” Schleicher said. “On the other hand, you don’t have good records from the past to really know what’s typical. “And I suspect this is a fairly common occurrence for Pons-Brooks, given the fairly large number of eruptions that have occurred in the last eight months.”
Comets are essentially lumps of dust, rock, and ice that are frozen remnants from the formation of the solar system. They also contain frozen elements such as carbon dioxide and carbon monoxide.
Schleicher said comets get hotter and brighter as they get closer to the sun, and some of the frozen gas stored in comets doesn’t need to heat up very much before turning into vapor.
“We think the biggest factor is, of course, the heating from the sun,” he said. “The comet is approaching; It had been sitting in the deep freezer for years. “The heat will travel from the surface to where carbon dioxide or carbon monoxide ice is present.”
Astronomers suspect that Pons-Brooks bursts occur during repeated events as heat vaporizes material inside the comet, causing pressure to build and the surface to rupture. Schleicher said a gas explosion wouldn’t be visible through telescopes, but the dust it would kick up would create the kind of events observed at Pons-Brooks.
Scientists traced jets of material released from the comet during its explosion to two source regions on its surface. Schleicher said astronomers were puzzled as to “why the entire surface wasn’t moving like crazy.”
Observations show that ice forms a crust over much of the surface, or the ice evaporates, leaving only dirt behind; but astronomers “are not exactly sure which of these mechanisms is running the show,” he said.
However, Kareta said the comet’s eruptions appear to have stopped and it has not shown any explosive activity since February.
What we can learn from comets
Astronomers observe Pons-Brooks in hopes of revealing more details about its spin rate, or the rate at which comets rotate as they move through space. Pons-Brooks’ rotation period is 57 hours, longer than expected, and astronomers want to know whether jets of material released from the comet are speeding it up or slowing it down.
A series of overlapping events likely contributed to Pons-Brooks’ distinctive appearance, but it could also be due to the way we view the comet, Kareta said.
“These are three-dimensional objects,” Kareta said. “When we take photos of the night sky, we’re taking them in a limited range of colors that are two-dimensionally flattened. This will make things that might be very meaningful to you look much more complex than they actually are, if you can get up and walk around and see them from a few different perspectives.”
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